Interplay of disorder and spin fluctuations in the resistivity near a quantum critical point

TL;DR

This paper investigates how disorder and spin fluctuations interact to influence the resistivity behavior in metals near an antiferromagnetic quantum critical point, explaining anomalous temperature dependence observed in certain compounds.

Contribution

It introduces a quasi-classical model showing how anisotropic spin fluctuation scattering combined with impurity scattering causes non-standard resistivity temperature dependence near a QCP.

Findings

Resistivity varies as T^alpha with 1 <= alpha <= 1.5 depending on disorder.

The mechanism explains anomalous resistivity in CePd_2Si_2, CeNi_2Ge_2, and CeIn_3.

Strong anisotropic scattering influences resistivity behavior near QCP.

Abstract

The resistivity in metals near an antiferromagnetic quantum critical point (QCP) is strongly affected by small amounts of disorder. In a quasi-classical treatment, we show that an interplay of strongly anisotropic scattering due to spin fluctuations and isotropic impurity scattering leads to a large regime where the resistivity varies as T^alpha, with an anomalous exponent, alpha, 1 <= alpha <= 1.5, depending on the amount of disorder. I argue that this mechanism explains in some detail the anomalous temperature dependence of the resistivity observed in CePd_2Si_2, CeNi_2Ge_2 and CeIn_3 near the QCP.